Ear pad



March 28, 1961 H. NOYES EI'AL EAR PAD 2 Sheets-Sheet 1 Filed June 25,1956 INVENTORS HOWARD NOYES BY EDWARD W. MOORMAN ATTORNEY March 28, 1961H. NOYES ETAL EAR PAD 2 Sheets-Sheet 2 Filed June 25, 1956 INVENTORSHOWARD NOYES EDWARD W. MOORMAN ATTORNEY United States atent Patentediviar. 28, 1961 EAR PAD Howard Noyes and Edward W. Moorman, Dayton,Ohio, assignors to Dayco Corporation, a corporation of Ohio Filed June25, 1956, Ser. No. 593,686

6 Claims. (Cl. 179-182) This is a continuation-in-part of ourapplication No. 518,573, filed June 28, 1955.

The present invention relates to heat and/or soundinsulating ear padsand particularly to such as may be employed to relieve fatigue andprovide comfort to the user in connection with acoustical devices suchas radio headphones and the like.

In the past, ear pads of one form or another have been employed for manypurposes including warmth, comfort, protection and the like, and pads orheadphones have been commonly employed for use in connection with radioreceivers particularly in aeronautics where it is required that thepilot be able to hear his radio at all times above the noises attendingthe operation of an aircraft while at the same time having his handsfree for such operation. These headphones have in the past involved arigid or semi-rigid diaphragm-carrying device, usually in the form of aflat cylinder which has been forced against the ear by a suitablehead-spanning clamp to cover the aural cavity, thereby leaving itexposed only to sounds coming through the headphones. While thisapparatus has proven satisfactory from the standpoint of acousticalrequirements, it has necessarily involved forcing the headphone againstthe ear resulting in its dis placement from its normal position; thisdisplacement has in turn resulted in discomfort and fatigue to the userof the same, particularly when use has been required for long periods oftime such as are now normally encountered in long range aircraftoperations.

In view of the disadvantages inherent in this form of headphone whichresulted in a dislocation of the car, more recent experiments have beenundertaken with regard to ear pads which are capable of carryingheadphones and which rest against the head of the user around his earrather than directly against the ear. Such pads have consisted of ashell of the general shape of a truncated semi-ellipsoid, the openportion of which has been designed to surround the ear of the user andto contact his head. The truncated portion is usually provided, in thecase of headphones on radio devices, with an opening which may beexposed to an audio signal. These pads can be made of such suflicientdepth that the ear of the user would not be deformed or displaced atall, and the hitherto experienced discomfort attending the use of theold type of phone has been eliminated. At the same time, however, it hasbeen found that while it is possible to obtain a satisfactory soundinsulation seal around the ear with the head-contacting portion of thepad, the Word intelligibility, i.e., the users ability to understandwords transmitted through the audio portion of the radio receiverassociated with the pad, has been considerably less satisfactory than inthe case of the previously employed headphones which actually press thetransmitter against the aural cavity. In addition, it has been foundthat previously developed pads have been so designed that they cannot beplaced over the ear simply and quickly by a direct thrust at rightangles to the ear. These pads are designed with undercut or recessedcavities in the aft portion in order that the aft portion of the helixof the ear may he slipped within the cavity. Thus it is necessary tobring the pad toward, but behind, the ear and subsequently bring itforward in order to allow that portion of the helix of the ear to fitwithin the cavity. Such a procedure is inefficient and awkward.

It is accordingly an object of the present invention to provide an earpad which may be worn for a considerable length of time withoutexcessive discomfort or fatigue resulting to the wearer.

It is a further object of the present invention to provide such a padwhich is suitable for use in connection with radio equipment.

Yet a further object of the present invention is to provide a pad foruse with radio equipment which will at once avoid the disadvantages of aheadphone in contact with the ear but will at the same time provide asatisfactory insulation of the aural cavity from exterior noises andwill allow a clear understanding of signals and messages beingtransmitted through the headphone associated with the pad.

Still another object of the invention is the provision of an ear padstructure which simplifies the step of placing the pad on the ear.

A further object is the provision of an aperture in the pad directlyover the opening to the inner ear.

These and other objects of the present invention, which will be apparentfrom a reading of the following disclosure, are achieved in the case ofthe present invention by utilizing the principle of a truncatedsemi-ellipsoidal device designed to surround the ear and contact thehead of the user adjacent the marginal portion of the ear. The presentinvention, however, provides for an important and critical modificationof the interior cavity defined by said device in that, instead of thepreviously employed cavity which merely conformed in shape to theexterior shape of the pad, there is provided herein an internal cavitywith built-up areas designed to render it substantially ear shaped orshaped in a manner conforming substantially to the shape of that portionof the human ear which projects or rises from the human head. Thepresent invention further provides for increasing the thickness of theshell at the head-contacting rim portion thereof, and also provides fora passage directly over the inner ear opening portion thereof. Theseexpedients result in a reduction of the internal volume of theear-receiving cavity of the pad with the unexpected result ofsurprisingly improved word intelligibility. In addition to thisreduction of interior volume, the increase in thickness of the shell atthe head-contacting portion thereof has resulted first in an improvedacoustical insulation of the aural cavity as well as a greaterdistribution of any stresses attending the wearing of the pads with aresultant increase in comfort to the wearer. The invention also providesfor a gradually decreasing area of the cavity toward the interior of thepad, without the usual undercut or recessed portion heretofore providedin similar devices in which the aft portion of the helix of the earfits. This permits a simpler procedure for the placing of the pad on thecar without the necessity of inserting the helix in a separate movement.

The invention thus generally described may be more clearly understoodfrom a study of the following detailed disclosure in connection withwhich reference may be had to the appended drawings, in which:

Figure 1 is an elevation of a conventional headset employed inconnection with radio equipment showing the manner of association of thesame with the human head.

Figure 2 is an exploded view in perspective of the individual componentsof the ear pad, illustrating their relationship.

Figure 3 is an elevational view of the complete ear pad.

Figure 4 is a section of the pad assembly taken along lines 4-4 ofFigure-3.

Figure 5 is another section of the pad assembly taken along lines 5-5 ofFigure 3.

Figure 6 is another section of the pad assembly taken along lines 6-6 ofFigure 3.

Referring now to Figure 1, a conventional headset referred to generallyby the numeral 10 consists of radio connections 11 and 12 which arewired by conduits 13 and 13a to supply a signal toreceivers l4 and 14a.The receii'ers are provided with flange portions, integral or otherwiseafiixed thereto, such as 15 and 15a which provide a base for receivingand-supporting. the pads 16 and 16a of the type used in one prefe rredembodiment of the present invention. The pad thus described may beincorporated in a headpiece such as a helmet or may merely be fastenedto a head-spanning clamp such as 17 for holding the pads and thereceivers associated therewith against the human head 18.

It is to be understood that the manner in which the pad of the presentinvention is fastened to or held against the head is not material to theinvention. Furthermore, the invention is not limited to the associationof the pad .with radio equipment since the pads may also be convenientlyemployed for heat as well as sound insulation purposes. In the lattercategory also will fall sound insulating pads which are not intended toprovide for any audible signal but are merely to prevent the wearer fromhearing annoying or fatiguing noises. Nonetheless, the pads according'tothe present invention do have particular utility when they areassociated with radio receiving equipment, in that they provide asatisfactory insulation of the audio signal from exterior noises and atthe same time do not interfere with the word intelligibility of thetransmitted message.

Referring now to Figure 2, the improved ear pad assembly consists of apad 19 and a supporting shell or rigid member 20. The pad is made of asemi-elastic or elastomeric composition of the type which is relativelysoft and comfortable to the touch while at the same time may be deformedwith relatively little force, yet recovers from the deformation slowly.The use of cellular or microporous compositions is especially preferredand has been found to improve the acoustical insulating properties ofthe pad. More specifically, the materials contemplated are foamedrubbers, synthetic rubbers such as polymers and copolymers ofchloroprene, butadiene, styrene and acrylonitrile; and plastics such aspolyamide, polyvinyl, and polyurethane resins. In contrast to the pad 19the supporting shell 20 is of the same general type of material but isso composed as to be considerably more rigid than the pad. Example ofthe material that might be used for the shell is polyurethane foamcompounded to be substantially rigid while a soft, flexible and elasticform of polyurethane foam may be used for the pad 19.

As shown in Figures 2 to 6 the pad 19 has a generally truncatedsemi-ellipsoidal exterior shape terminating in a head-contacting rim 21which is substantially elliptical when viewed as in Figure 3. This rimis of a greater thickness than the remainder of the pad in order toprovide a greater mass of acoustically insulated material. Theinsulating effect is further enhanced by the width of this rim andfurther provides for insulating by an increased width and mass of therim at the portion 22 which would lie adjacent the tragus of the ear.From the exterior of the cavity at the rim, the cross-sectional area ofthe cavity decreases constantly from a maximum at the rim to a minimumat 24, which is the point farthest from said rim (as best shown inFigure 4). By exterior is meant that portion of the cavity closest tothe rim in contrast to the interior of the cavity meaning 4 that portionfarthest from the rim. The forward portion 23 of the cavity decreasesmore gradually than the aft portion, which rises almosti at right anglesto the rim of the cavity in order to accommodate the aft portion of thehelix of the car. It is thus possible to place the pad directly over theear in a motion at right angles to the head in order to accommodate theear with a minimum of discomf rt or distortion of the ear. At the sametime the interior volume of the cavity is such that there is no excessvolume, resulting in an improvement in word intelligibility when the padis employed for audio signals. In order to provide a passage for thesound waves from the audio receiver 14, an opening 25 is providedpassing through the entire depth of the pad and is located in theinterior wall 23 of the cavity. The opening 25 is so located that whenthe pad is placed over the ear the opening is in direct line with thepassage from the outer ear to the inner ear in order to provide a highlyefiicient transmitting means.

The supporting shell 20 has a semi-ellipsoidal shape =27 which conformsexactly to the outer surface 26 of the pad in order that they may beplaced in juxtaposition with each other for permanent bonding. The shellmay be adhered to the pad along the mating surface 26 and 27 by means ofsuitable adhesives or such mechanical means as rivets or the like.Although the method of forming the shell 20 is not contemplated withinthe scope of my invention, it may be specifically suggested that truemating surfaces be achieved between it and the pad by using the samemold to form both members, as is well known in the field of molding thetype of material being herein used.

An opening 28 in the shell is provided to align perfectly with theopening 25 in the pad, the opening pass ing completely through the shellto provide a continuous passage through both members. The outer surfaceof the shell includes a boss 29 in which is found a recess 30 conformingin shape to the receiver '14. The receiver may be placed within therecess and aifixed to flange 15 by screws, belts, or other conventionalmeans so that the diaphragm of the receiver will transmit its wavesthrough the openings 28 and 25 into the ear.

Although specific details of the invention have been described, thesedetails are considered exemplary and are not intended in any way tolimit the scope of the invention. Modifications in these details may bemade without departing from the spirit of the invention. For example, ifthe device is to be used for heat or sound insulation purposes, theopenings 28 and 25 will be unnecessary.

We claim:

1. A receiving headset for audio signals comprising an acousticallyinsulating cushioning pad and a supporting member attached thereto, saidpad having a head-corn tacting rim defining a cavity conforming in shapeto that portion of the car which projects from the head, the portion ofthe rim adapted to be placed adjacent the .tragus of the ear having asubstantially greater width than the remainder of the rim.

2. A receiving headset for audio signals comprising a pad ofacoustically insulating cushioning material and a supporting memberattached thereto, said pad having a head-contacting rim defining acavity conforming in shape to that portion of the ear which projectsfrom the head, the portion of the rim adapted to be placed adjacent thetragus of the ear having a substantially greater mass of material thanthe remainder of the rim. 7

3. A receiving headset for audio signals comprising an acousticallyinsulating cushioning pad and a supporting shell attached thereto, saidpad having a head-contacting rim defining a cavity therein conforming inshape to that portion of the car which projectsfrom the head, thecross-sectional area of said cavity decreasing from a maximum at saidrim to a minimum at a point farthest from said 4. A receiving headsetfor audio signals comprising a pad of acoustically insulating cushioningmaterial and a supporting shell attached thereto, said pad having aheadcontacting rim defining 'a cavity therein conforming in shape tothat portion of the ear which projects firom the head, thecross-sectional area of said cavity decreasing from a maximum at saidrim to a minimum at a point farthest from said rim, and openings in saidpad and shell in alignment with each other and the passage of the outerto the inner ear.

5. A receiving headset for audio signals comprising a pad ofacoustically insulating cushioning material having a generally truncatedsemi-ellipsoidal exterior surface and a supporting shell of the sametype of material having an interior surface conforming to and attachedto the exterior surface of said pad, said pad having a head-contactingn'm defining a cavity therein conforming in shape to that portion of theear which projects from the head, the cross-sectional area of saidcavity decreasing from said rim to a point farthest from said rim, theportion of the rim adapted to be placed adjacent the tragus of the earhaving a substantially greater width than the remainder of the rim.

6. A receiving headset for audio signals comprising a pad ofacoustically insulating cushioning material having a generally truncatedsemi-ellipsoidal exterior surface and a supporting shell of the sametype of material having an interior surface conforming to and attachedto the exterior surface of said pad, said pad having a headcontactingrim defining a cavity therein conforming in shape to that portion of theear which projects from the head, the cross-sectional area of saidcavity decreasing from a maximum at said rim to a minimum at a pointfarthest from said rim, the portion of the rim adapted to be placedadjacent the tragus of the ear having a substantially greater width thanthe remainder of the rim; openings in said pad and shell in alignmentwith each other and the passage of the outer to the inner ear, and anaudio receiver affixed to and adjacent the opening in the shell topermit audible signals to be transmitted to the ear.

References Cited in the file of this patent UNITED STATES PATENTS2,353,070 Pitkin July 4, 1944 2,407,731 Woodruif Sept. 17, 19462,468,721 Volkmann Apr. 26, 1949 2,474,386 Volkmann June 28, 19492,501,830 Ruml Mar. 28, 1950 2,529,562 Martin Nov. 14, 1950 2,802,214Hanks Aug. 13, 1957

